The present invention relates to a sealed container for containing milk, juice or the like.
Such sealed containers heretofore known include one which comprises a rectangular parallelepipedal container main body 11 provided with two upper and two lower triangular ears 12 and 13 at its upper and lower ends, respectively as seen in FIGS. 4 to 8. When seen from above, the container main body 11 has a larger dimension in the transverse direction perpendicular to the front-to-rear direction indicated by an arrow A in FIG. 4. The main body has a front side 14, rear side 15, opposite lateral sides 16, 17, top side 18 and bottom side 19. The upper triangular ear 12 is integral with the lateral side 16 (17) and the top side 18 at the upper ridge 21 (20) wherebetween, folded downward along the ridge 21 (20) and lapped over and adhered to the lateral side 16 (17). The lower triangular ear 13 is integral with the lateral side 16 (17) and the bottom side 19 at the lower ridge 23 (22) therebetween, folded inward along the ridge 23 (22) over the bottom side 19 and adhered thereto. Stated briefly, this container is formed by a known method comprising the steps of preparing a tube from a web of laminate composed of a paper base sheet and a thermoplastic synthetic resin layer on each surface of the base sheet by lapping the opposite longitudinal edges of the web over each other and sealing the lap, forming an unfinished intermediate container V-shaped in cross section at its upper and lower portions by sealing the tube transversely thereof to obtain a container portion after filling contents into the tube and cutting the sealed area at the center of its width, and making the intermediate container into a complete container by shaping the upper and lower portions flat while forming triangular ears at these portions and folding and adhering the upper and lower triangular ears as stated above. The upper and lower transverse seal portions 24 and 25 formed by transversely sealing the tube extend sidewise over the top side 18 and the bottom side 19, respectively, and further extend at the opposite ends of the container over the upper and lower triangular ears 12 and 13 to the apexes of the triangles. The longitudinal seal portion 26 formed by lapping the longitudinal edges of the web over each other and sealing the lap extends vertically over the rear side 15 at the center of its width, further extends at the upper and lower ends of the rear side 15 over the top side 18 and the bottom side 19 and intersects the upper and lower transverse seal portions 24 and 25 at the opposite ends of the seal portion 26. As shown in detail in FIG. 7, the longitudinal edges 28 and 20 of the container blank providing the longitudinal seal portion 26 are lapped over and joined to each other. Accordingly, if the face 30 of the inner edge 28 is left exposed inside the container, the contents will penetrate into the material of the container through the edge face 30. To prevent this, a seal tape 31 is provided over the lap for covering the edge face 30.
The upper and lower transverse seal portions 24 and 25, which are upstanding and depending when formed by sealing, are folded forward and have their end faces 32 and 33 directed forward. This poses the following problems. First, when the container is seen from the front as shown in FIG. 6, the above-mentioned end faces 32 and 33 directly come into view, rendering the container unsightly. The second problem arises from the upper and lower intersections of the longitudinal seal portion 26 with the upper and lower transverse seal portions 24, 25. With reference to FIG. 8 typically showing the upper intersection, the upper transverse seal portion 24, which was upstanding on sealing, is folded forward, with the result that the seal tape 31 included in the intersection is also folded. The seal tape 31 is folded in such a direction as to loosen the tape 31. The seal tape 31, if loosened, permits the contents to leak and penetrate into the material of the container.